A Generalized Analysis of the Regenerative Steam Cycle for a Finite Number of Heaters

Abstract

The paper establishes a theoretical basis for approximate relationships which have been found to apply to feed heating calculations for a wide range of operating conditions. The designer, looking for short-cut methods in the calculation of multistage feed heating problems, will not find sufficient accuracy in the approximations to satisfy his more precise requirements. Other papers† have already catered for such requirements, but it is hoped that the present paper will give the designer and student a more complete understanding of the problem.

The determination of the optimum range of feed heating, and the improvement in heat consumption due to feed heating at the optimum condition, for a system employing n feed water heaters is investigated in the paper. A simple approximate relation is derived for these two quantities by expressing them non-dimensionally in terms of the respective quantities for a system employing an infinite number of heaters. The optimum distribution of heating amongst the heaters in the system is also determined analytically.

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